Li-rifuas Chaim Dov ben Risa Shoshana bi-soch shear cholei yisrael!!!
The Mishna [Bava Metzia 33b] says that if a shomer was given property which was subsequently lost and he opted not to swear [that he wasn't negligent and that he didn't use it for himself] - when the thief is found he pays the כפל to the shomer and not to the owner .
The gemara asks how can the mafkid could be מקנה the keifel [which originally was coming to him]?? When the shomer took the animal, the keifel didn't yet exist, making it a davar shelo ba la-olam and the rule is that a person cannot sell or acquire a davar shelo ba la-olam?! The gemara's answer is that it is as if the mafkid said to the shomer that if you decide to pay then the animal is yours from the outset [thus it is not a davar shelo ba li-olam because the animal which already existed, belonged to the shomer when it was stolen and the keifel is coming to him already at that stage]. So the way he gets the keifel is by vitually taking ownership of the animal from the get go..
Fregt the Raavad in the Shittah Mekubetzes: I have a BETTER idea!! You don't have to come on to the notion of the keifel coming to the shomer because the mafkid was makneh him the animal and keifel from the very beginning. Instead say that the shomer himself is the owner of the animal! Why? Since he is financially responible for the animal and everybody and their Aunt Gerta knows the rule of Rav Shimon that "davar hagoreim li-mamon kimamon domi", meaning that having a monetary stake in an object, renders him owner! Since it is goreim limamon - it causes him to have to pay - it is like his mamon and thus as if he owns it. So THAT should be the reason he gets the keifel!!
He answered that the gemara understands that the din of davar hagoreim etc. applies only when he has FULL responsibility and in the case of the shomer there is not full responsibility because in certain instances the shomer need not pay [such as אונס]. That is why the gemara was compelled to offer the answer that it is as if the mafkid gave him rights to the animal from the outset in the event that it is lost and he declines to swear.
Added Rav Dovid Povarsky ztz"l, Rosh Yeshivas Ponovitch: When the gemara in Pesachim says that when one takes financial responsibility for chometz, he is עובר on Bal Yairaeh because of the rule of davar hagoreim etc. - when now know that means that he takes FULL responsibilty and not partial responsibility.
Li-darkeinu lomadnu 2 lessons:
1] When you are learning Bava Metzia never forget to check for nafka minahs with respect to Pesach - and every other area of halacha.
2] In order for something to be considered monetarily yours by dint of the rule of davar hagoreim limamon kimamon domi, one must take FULL responsibility. In life, people often shirk responsibility. A sign of emotional and spiritual maturity is to take FULL responsibility, not partial or none!:-)
והראב"ד בשטמ"ק הקשה, לר"ש דאמר דבר הגורם לממון כממון דמי, א"כ כיון דהשומר חייב באחריותה, ליחשביה כבעלים, [ולמה לן טעמא דהכפל להשומר משום דהבעלים מקנה לו הכפל, תיפו"ל דהוא מצד עצמו חשיב הבעלים, מחמת דין גורם לממון, וא"כ יתחייב הכפל ישר להשומר].
ותירץ דלא דמי חיוב שמירה לאחריותה דבהמה, משום דבשמירה איכא אנפי דלא מיחייב, ואחריות בכל אנפי מיחייב עלה, ע"כ.
והיינו דסובר דדין גורם לממון כממון דמי הוי רק אי הוי עליו "כל" האחריות, ולכן בשומר, דאיכא אופנים דאינו חייב, ליכא דין גורם לממון כממון דמי.
ולפי דבריו, הא דאמרינן בפסחים (דף ה ב) דחמץ שקיבל עליו אחריות, נמי עובר בבל יראה, ומדמה זה לדין גורם לממון כממון דמי, א"כ התם נמי רק בחיוב אחריות גמור בכל האופנים, עובר בבל יראה.